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to gnaw; to nibble; to bite; to munch; to crunch
to dabble in; to know a little bit about; to learn a little of; to have a smattering of
犬が骨を齧っているのを見て微笑んだ。
I smiled seeing the dog gnawing on a bone.
ネズミが箱の角を齧った跡があった。
There were marks where mice had gnawed the corner of the box.
フランス語を少しだけ齧ったことがあるから読める。
I dabbled a bit in French, so I can read it.